Ion Irradiation De-coating of PCD Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current de-coating methods for tools coated with inorganic materials like PCD face inefficiencies due to uneven ion irradiation leading to dead areas and brittle phase formation, and often require environmentally unfriendly chemicals or high temperatures.
Innovation Solution
A de-coating method using ion irradiation with a bias voltage applied to the substrate to concentrate ion flows and prevent deflection, performed at ambient temperature to avoid brittle phase formation, and using a combination of oxygen and argon plasmas to efficiently remove coatings without causing substrate embrittlement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If ion irradiation is used for de-coating, then de-coating efficiency is improved, but dead areas occur due to uneven ion irradiation
Solution Approach 1:
The patent divides the ion irradiation process into multiple directions by using multiple ion beam sources positioned at different angles. This segmentation of the irradiation approach ensures that all surfaces of the coated body receive sufficient ion exposure, eliminating dead areas while maintaining high de-coating efficiency.
Solution Approach 2:
The patent transitions from single-direction ion irradiation to multi-directional ion irradiation by positioning beam sources at various angles around the coated body. This dimensional change in irradiation approach ensures uniform coverage of all surfaces, including recessed areas, thereby eliminating dead areas and improving de-coating uniformity.
2Productivity
If high temperature treatment is used for de-coating, then de-coating speed is improved, but brittle phase formation occurs in the substrate
Solution Approach 1:
The patent replaces thermal energy with kinetic energy of ions for the de-coating process. By using ion bombardment instead of high temperature heating, the method achieves efficient de-coating through physical sputtering while avoiding thermal effects that cause brittle phase formation in the substrate.
Solution Approach 2:
The patent changes the fundamental parameter of energy delivery from thermal (temperature) to kinetic (ion beam energy). This parameter change enables effective de-coating through ion bombardment at room temperature or low temperatures, eliminating the trade-off between de-coating speed and substrate integrity that exists with thermal methods.
3Area of stationary object
If plasma irradiation is used for de-coating, then coverage is improved, but de-coating efficiency decreases due to sheath formation
Solution Approach 1:
The patent inverts the conventional plasma irradiation approach by using low-pressure ion beam sources that generate directed ion flows rather than diffuse plasma. This inversion eliminates sheath formation while maintaining wide area coverage, as the ion beams can be directed to cover large surfaces uniformly without the space electrical layer barrier that hinders de-coating action.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively recycles tools by minimizing dead areas and preventing brittle phase formation, allowing for efficient and economical de-coating of PCD coatings without damaging the substrate, enabling easy re-coating and reducing environmental impact.
Implementation Method 1
exposing a coated body to ion flows to peel off a coating
Implementation Method 2
a combination of oxygen and argon plasmas
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A de-coating method capable of recycling a tool or a mechanical part coated with an inorganic material such as PCD (poly-crystalline diamond) is provided. According to the de-coating method, a substrate to be subjected to de-coating (coated body) is less likely to have a dead area during ion irradiation, a brittle phase is less likely to be formed in the substrate (metal body) in terms of temperature, and de-coating can be performed at an economical speed. The problems can be solved by the de-coating method including: exposing the coated body in which a coating made of an inorganic material is formed on a surface of the metal body to ion flows to peel off the coating from the metal body, wherein the coated body is placed at an ion flow-concentrated portion where two or more ion flows overlap each other, and is exposed to the ion flows without addition of a positive or negative bias to the coated body. As gases for use in generating ions from plasma, oxygen and CF4 that promote de-coating through a chemical reaction are preferably used in addition to Ar that performs de-coating under the physical action of ion collision and stabilizes plasma.